EgressRoute now extends egress_addon_core.Route, which holds the four
wire-visible fields (host, path_allowlist, auth_scheme, token_env).
EgressRoute adds only the three host-side fields (token_ref, roles,
tls_passthrough) that are never serialised to the sidecar.
_route_to_yaml_fields is typed as Route -> dict, making the host→wire
boundary explicit: only fields declared on the base class cross into the
YAML the addon reads.
Replace _merge_provider_route's five-case nested conditional with a flat
provisioned-wins merge: provider routes claim their hosts outright, manifest
routes for unclaimed hosts append unchanged. Token slot assignment moves to a
single _assign_token_slots pass over the merged list.
Add _route_to_yaml_fields as the single authoritative EgressRoute→YAML mapping,
eliminating the risk of EgressRoute and egress_addon_core.Route silently
drifting apart when new fields are added.
egress_manifest_routes is now a pure lifter with no slot assignment.
_merge_provider_route and _find_or_alloc_token_env are removed.
Tests updated: conflict-die case removed, upgrade-bare replaced with
provider-wins semantics, slot-assignment tests moved to TestSlotAssignment.
Expands scope to cover both remaining egress hotspot tasks from #117:
- Replaces the named-helper design with a flat provisioned-wins merge
(provider routes own their hosts; manifest fills gaps; no upgrade or
conflict-detection logic needed).
- Adds _route_to_yaml_fields as the single authoritative EgressRoute→Route
mapping to prevent silent type drift between host and addon.
- Notes that the mitmproxy pure-function split is already clean (decide +
is_git_push_request) and requires no structural change.
didericis-claude